Enclosure system allowing for hot work within the vicinity of flammable and combustible material

ABSTRACT

A system, that incorporates one or more enclosures constructed around one or more objects at which, “hot work” is to be performed at a facility at a first location containing flammable or combustible materials. The one or more enclosures are capable of being simultaneously and independently controlled and monitored by a single control and monitoring system which is capable of being in radio communication with a control system at a second, but remote, location.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. Ser. No. 11/176,495filed Jul. 7, 2005 now U.S. Pat No. 7,193,501 which is acontinuation-in-part of U.S. Ser. No. 11/011,848 filed Dec. 14, 2004 nowU.S. Pat. No. 7,091,848 issued on Aug. 15, 2006 which is acontinuation-in-part of U.S. Ser. No. 10/388,271 filed Mar. 13, 2003 nowabandoned.

FIELD OF THE INVENTION

The present invention relates to a system, that incorporates one or moreenclosures constructed around one or more objects at which, “hot work”is to be performed at a facility at a first location containingflammable or combustible materials. The one or more enclosures arecapable of being simultaneously and independently controlled andmonitored by a single control and monitoring system which is capable ofbeing in wireless communication with a control system at a second, butremote, location.

BACKGROUND OF THE INVENTION

Hot work, such as welding, at facilities where flammable and combustiblematerials are present, is extremely dangerous and is regulated by theappropriate governmental agency depending on the facility. In the caseof offshore platforms, hot work is regulated by the Mineral ManagementService (MMS); in the case of a pipeline, pumping stations andassociated facilities, hot work is regulated by the Department ofTransportation (DOT) and in the case of refineries and chemical plants,hot work is regulated by the Occupational Safety and HealthAdministration (OSHA). Regulations stipulate that hot work cannot bepreformed in or on any of said facilities within 35 feet from the pointof impact where slag, sparks or other burning materials could fall ontoor in the vicinity of a storage area of a container containing flammableor combustible materials. Also, hot work cannot be preformed within 10feet of a pressurized pipe or vessel containing flammable or combustiblematerial in or on any of said facilities.

In some cases, the hot work operation can be setup in a safe area anditems to be hot worked can be brought to this safe area, hot worked, andthen returned to their original location. In most cases it is notpractical, from a strategic or from an economic point of view, to setupa remote hot work location a distance away from the item that needs tobe hot worked. In the past, a facility such as a petroleum productionplatform, would have to be shut down during hot work operations.Further, a section of pipe or vessel in a petroleum refinery or chemicalplant would have to be purged and cleaned of flammable and combustiblematerial before any hot work could be performed within 10 feet of it.This created a substantial financial burden for the operator of theplatform or plant.

A welding habitat was developed within the last few years wherein atemporary building was built around an object to be hot-worked. Thehabitat, also referred to as an enclosure, is equipped with gasdetection monitors that would automatically signal a shut down of allwelding equipment when a predetermined concentration level of flammableor combustible gas is reached. For example, U.S. Pat. No. 6,783,054 toPregeant Jr. et al. teaches and claims a system for conducting weldingadjacent flammable materials on an offshore platform. The systemcontains an enclosed chamber having a blower and sensors, each of whichmonitors a single gas, typically a combustible gas, and the ability toautomatically shutdown the welding operation if a predeterminedunacceptable concentration of a combustible gas is detected at one ormore sensors.

U.S. Pat. No. 7,091,848 to Alford Safety Services, Inc and co-pendingpatent application Ser. No. 11/176,495 teach habitat systems allowingfor hot work to be performed within the vicinity of flammable andcombustible materials. The hot work is monitored and controlled thoughthe use of gas detectors and central processing units, but there is noprovision for data being transmitted to a remote location or for thesystem to be controlled from a remote location.

While the industry is starting to see habitat and monitoring systemsthat enable hot work to be preformed in areas here-to-fore not allowedunless the facility was shut-down, there is still a need in the art forimproved hot work enclosures and monitoring and control systems thatlead to a more economical and safe hot work operation.

SUMMARY OF THE INVENTION

In accordance with the present invention there is provided an enclosuresystem comprised of one or more enclosures built about at least oneobject to be hot worked at a facility wherein flammable or combustiblematerials are located within a hazardous distance from where the hotwork is to be performed, which enclosure system is comprised of:

-   a) at least one enclosure, each enclosure comprising: i) enclosing    walls, ceiling and floor defining a chamber in which the hot work is    to be performed; ii) at least one door to allow workers to enter and    exit; iii) at least one air inlet port; iv) at least one air outlet    port; v) at least one blower having an intake and exhaust, which    exhaust is in fluid communication with said at least one air inlet    port; vi) a blower control in communication with said at least one    blower and to a gas detection monitor at the intake of at least one    of said one or more blowers and to a shutdown controller, wherein    said blower control has the capability of allowing the blower to    continue to operate during an emergency shutdown that is not    triggered by a combustible or flammable gas detected at a gas    detection monitor located at the intake of said one or more    blower; vii) at least one manual emergency shutdown switch inside of    said enclosure; and viii) at least one manual emergency shutdown    switch outside of, but within the immediate perimeter of, said    enclosure;-   b) a monitoring system comprised of:    -   i) a plurality of gas detection monitors located at the        predetermined locations inside and outside of each enclosure;        wherein each of said gas detection monitors having a means of        communication with a gas detection controller console; and    -   ii) a gas detection controller console comprised of: a) a means        capable of receiving data transmitted from the plurality of the        gas detection monitors; b) an interface means capable of        communicating data from the said receiving means of the console        to a central processing unit; c) the central processing unit        containing software capable of, inter alia, accepting, storing        computing, and displaying data received from said plurality of        gas detection monitors; d) a display device in communication        with said central processing unit and capable of displaying data        from said plurality of gas detection monitors; and e) an        interface means capable of communicating a signal from said        central processing unit to a control system;-   c) the control system comprised of:    -   i) an operator controller console comprised of: a) a source of        electrical power for the system; b) at least one control        device; c) a means for displaying the status of each        enclosure; d) a capability of communicating predetermined bypass        and system shutdown signals to a shutdown controller; and e) an        audible alarm that will activate when a shutdown occurs;    -   ii) a shutdown controller capable of sending shutdown signals to        one or more enclosure control devices, one or more shutdown        control devices, and to various equipment associated with the        hot work to be conducted in said one or more enclosures;    -   iii) an enclosure controller comprised of a differential        pressure monitor for monitoring the pressure within the        enclosure relative to the pressure outside of the enclosure, a        programmable logic control device, an audible alarm and a visual        alarm; and    -   iv) a controller console at a remote location and in wireless        communication with said operator controller console and shutdown        controller, which controller console is capable of performing        all the functions of said operator controller console and which        is also capable of downloading software said central processing        unit and programmable logic control device.

In a preferred embodiment the wireless communication is performed via alink to a communications satellite.

In a preferred embodiment, said at least one enclosure also comprisesone or more of the following: a) a power control; b) a temperatureprobe; c) a temperature detector; d) emergency lights; or e) a cablesealing system.

In another preferred embodiment, there is provided, devices for wirelesscommunication between the operator controller console, the shutdowncontroller and the one or more enclosure controllers.

In another preferred embodiment, the components of the gas detectioncontroller console are integrated into the operator controller console.This new console serves as a system console and utilizes a separatedisplay device for viewing the readings of the plurality of the gasdetection monitors.

In another preferred embodiment, the DPM in any one or more enclosurecontrollers contains a manual gauge and/or a generated signal for ascaled readout of the current reading of the DPM, on a display device.

In another preferred embodiment, the operator controller console alsohas the ability to bypass the shutdown function of a differentialpressure monitor (DPM) at each of the said at least one enclosures bythe use of a manual or logic (PLC) switch.

In another preferred embodiment, the operator controller console alsohas the ability to bypass the shutdown function of a differentialpressure monitor (DPM) at each of the said at least one enclosures bythe use of a manual or logic (PLC) switch and an automatic, temporarybypass program.

In another preferred embodiment, there is provided devices for poweringthe components of the shutdown controller and the enclosure controllers,via solar power.

In another preferred embodiment, the hot work is selected from welding,cutting, and grinding.

In another preferred embodiment, the facility is a petroleum drillingplatform, a petroleum production platform, a jack-up rig, a pumpingstation, a petroleum refinery, a tank farm, a chemical plant, an oceangoing tanker, or a section of a pipeline.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 hereof is schematic representation of one preferred embodiment ofthe monitored enclosure system of the present invention showing threeenclosures that can be simultaneously and independently monitored andcontrolled. This schematic shows the use of both a wireless gasdetection system and some hard wired gas detection monitors used toimplement an automatic blower control concept, a control system; whichuses software programmed controllers and further utilizes an operatorcontroller console; which uses a display device and for controlling somepredetermined control functions. Data from the operator controllerconsole is transmitted to a remote control console via a communicationssatellite link.

FIG. 2 hereof is a schematic representation of another preferredembodiment of the monitored enclosure system of the present inventionalso showing three enclosures capable of being simultaneously andindependently monitored and controlled. This system utilizes most of thecomponents of the enclosure system of FIG. 1 with the followingexceptions and additions: the use of only a wireless gas detectionsystem wherein the components of the gas detection controller consolehave been integrated into the operator controller console serving as asystem console. This gas detection system allows for the implementationof the automatic blower control concept with an all wireless system.This figure also shows the integration of a camera and sensor moduleinside of the enclosure controllers. The camera is used for viewing thehot work being performed inside the enclosure and the sensor module fortaking readings of variables such as temperature and humidity inside ofthe controllers. Another feature represented by this FIG. 2 is the useof a temperature probe and a temperature detector. The temperature probeis for monitoring the ambient temperature inside of the enclosure andthe temperature detector is used to detect the temperature of an objectbeing worked on inside the enclosure. Furthermore a “fire-eye,” or arcsensitive switch is incorporated in part of the implementation of anautomatic DPM bypass concept wherein the DPM will have a timed automaticbypass feature unless there is hot work being performed inside of theenclosure.

FIG. 3 hereof is a schematic representation of another preferredembodiment of the monitored enclosure system of the present inventionalso showing three enclosures capable of being simultaneously andindependently monitored and controlled. This system utilizes componentsof the enclosure system of FIG. 1 hereof with some additional componentsadded into the operator controller console, shutdown controller andenclosure controllers, for implementing wireless communication betweenall the controllers in the system. The use of a plurality of remoteantenna boxes is also disclosed, as they are needed in providingcommunication between the controllers in the control system.

FIG. 4 is a diagram representation of one preferred embodiment of aconfiguration of the enclosure controllers utilized in the systemdisclosed in FIG. 1.

FIG. 5 is a diagram representation of one preferred embodiment of aconfiguration of the enclosure controllers utilized in the systemdisclosed in FIG. 2.

FIG. 6 is a diagram representation of one preferred embodiment of aconfiguration of the enclosure controllers utilized in the systemdisclosed in FIG. 3.

FIG. 7 is a diagram representation of one preferred embodiment of aconfiguration of the enclosure controllers utilized in the systemdisclosed in FIG. 4.

DETAILED DESCRIPTION OF THE INVENTION

The present invention can be utilized for any type of hot work and atany facility where flammable and/or combustible materials present asafety issue during hot work operations. The term “hot work” as usedherein, means any work or operation, which could produce spark, flame orexcessive heat resulting in a fire or explosion in the presence ofcombustible or flammable materials. Non-limiting examples of the typesof hot work that can be conducted in the enclosures of the presentinvention include all types of welding, such as gas welding, electricarc welding and cutting, including gas tungsten arch welding (GTAW), gasshielding metal arch welding (GMAW), friction welding, laser welding,cutting such as with a torch or plasma cutter and cutting, brazing,soldering, and grinding with electric and pneumatic tools. Alsoincluded, is working in electrical panels while they are still energizedin a location of the said facility considered to be classified, inreference to the presence of flammable or combustible materials, by afacility area classification drawing.

The present invention can be practiced at any type of facility where hotwork is to be done in the vicinity of flammable or combustible material.Non-limiting examples of facilities where the instant invention can bepracticed include petroleum drilling and production platforms, includingjack-up rigs; pumping stations; petroleum refineries; chemical plants;tank farms where flammable or combustible materials are stored; andtankers and pipelines used for transporting flammable or combustiblematerials. As previously mentioned, governmental regulations are strictwith respect to performing hot work at such facilities. In the past, atleast a portion of such a facility would have to be shutdown prior toperforming any hot work operation.

Practice of the present invention allows for safe and efficient hot workto be performed in the vicinity of flammable and combustible materials.At least one enclosure, also sometimes referred to herein as a habitat,is built around the object or objects to be hot worked. The enclosure isof temporary construction comprised of enclosing walls, ceilingextending between the walls and floor extending between the walls,thereby defining a chamber. It can take any shape depending on theobject or objects to be hot worked and the particular site limitationsat which it is to be built. Any material suitable for constructing suchan enclosure can be used. Non-limiting examples of suitable constructionmaterials include metals, ceramics, wood, and composite materials suchas fiberglass and carbon fiber reinforced polymeric materials. Fireretardant wood is preferred, more preferably plywood, for thecombination of safety, cost and convenience purposes. Scaffolding, ifneeded, can be provided to support at least a portion of each enclosure,particularly if the enclosure needs to be positioned lateral to aproduction or drilling platform. The enclosure will be large enough toallow a predetermined number of workers to comfortably work inside theenclosure with all necessary tools, hot work equipment and monitoringand safety devices. At least two workers will typically be in a singleenclosure. If only two workers are provided, one worker will be the oneperforming the hot work and the other worker will typically be on firewatch for observing the hot work. Workers inside of the enclosure willhave the capability of verbally communicating with the operator andworkers outside of the enclosure by use of conventional means,preferably by two-way wireless radio.

Each enclosure will contain at least one door that preferably opens tothe outside of the enclosure. The door will be one that can be easilyopened from both the inside and outside of the enclosure and built in abreak-away fashion, in case of an emergency. At least one shatterproofviewing window will be present on either the door or on one or morewalls for observing activity within the enclosure. Shatterproof windowsare well known in the art and are typically manufactured as laminatedglass with an inner layer of transparent plastic material. All plasticviewing windows can also be used for the instant enclosure. The floor ofeach enclosure will preferably be lined with a suitable material capableof withstanding temperatures up to about 3000° F., preferably up toabout 3500° F. Such a floor will preferably be comprised of a bottomlayer of fire retardant plywood covered with a refractory clothmaterial. The cloth material, which will typically be supplied in rollsof ⅛ to ¼ inch thickness, is of the type marketed by ThermostaticIndustries Inc. of Huntington Beach, Calif., under the trade-namePanther Felt. Such a material is comprised of a refractory fiber, suchas fiberglass or a ceramic fiber such as aluminosilicate oraluminoborosilicate. On top of the cloth layer will preferably be arelatively thin malleable layer of sheet metal material, preferably astainless steel, to safely contain slag or sparks generated from the hotwork operation. The floor will also preferably contain side plates (notshown) around the periphery of the floor to help contain sparks andslag. The side plates will typically be several inches to about a footoff the floor.

Each enclosure will also contain at least one inlet port to allow asuitable amount of air to be conducted into the enclosure by use of ablower, preferably an electrically operated blower. At least one airoutlet port will also be provided. It is preferred that each air outletport contain a spark resistant grill or filter to substantially reducethe potential of sparks being carried from inside of the enclosure tothe outside where flammable or combustible materials may be present.Another preferred way of minimizing the risk of sparks and slag fromexiting the enclosure at a high temperature is to provide a metalventilation duct system (not shown). Such a system will be of sufficientlength leading to the spark resistant filter so that any sparks or slagentering the ventilation system in the enclosure will cool to a safetemperature if they should ever reach the filter, and get through to theoutside atmosphere.

Each enclosure, while in use, will be under a positive pressure toprovide fresh air to workers inside the enclosure and to prevent gasesfrom outside the enclosure from entering the interior of the enclosure.The pressure of each enclosure is monitored by a suitable differentialpressure monitor (DPM), which is preferably an integral component of theenclosure controller. The present invention provides for the monitoringand control of multiple enclosures by a single operator using a singlemonitoring system and a single control system wherein multipleenclosures can be individually or all can be simultaneously shutdown, orcertain equipment can be selectively bypassed if one or morepredetermined events occur. Of course only a single enclosure can bemonitored and controlled by the practice of the present invention.

It will be understood that each enclosure will also have an enclosurecontroller represented in FIGS. 4-7 hereof. The enclosure controllerwill be an integral unit containing such things as: a) a differentialpressure monitor (DPM); b) at least one control device preferably aprogrammable logic controller; c) an audible alarm; d) a visual alarm;e) a backup battery system; f) a manual shutdown switch; g) a cameramodule; h) a component sensor module; i) a radio transceiver; and j) aremote control panel, preferably of the touch screen type. A basicenclosure controller will contain a DPM, at least the one controldevice, an audible alarm, and a visual alarm. The next more complexenclosure controller can contain manual shutdown switch and/or a backupbattery. The enclosure controller(s) for an all wireless system wouldalso include a radio transceiver.

It will also be understood that each enclosure will also have aconventional explosion proof lighting system supported by a backupbattery system, so that lighting inside each enclosure will continue tofunction during an emergency shutdown. A conduit sealing system willalso be used to create a proper seal for sealing any spaces aroundcables, hoses, and pipes entering an enclosure from the outside.

The present invention will be better understood with reference to thefigures hereof. FIG. 1 is a simplified schematic of one preferredembodiment of the present invention showing three enclosures systemswherein welding is the hot work to be performed in any one or more ofthe enclosures. All three enclosures are managed by a single operatorusing a single monitoring system, preferably a single wireless gasdetection monitoring system, and a single control system. FIG. 1 showsthree enclosures E1, E2, and E3, each having at least one door D1, D2,and D3, at least one air inlet port IP1, IP2, and IP3, and at least oneair outlet port OP1, OP2, and OP3. It is preferred that the door openoutward and that it be a break-away door. That is, a door constructed insuch a way that in the event of an emergency a single worker of averagestrength could exert enough force so that the door breaks away from itssupport means and provides the worker with a means of escape.

In one embodiment the one or more of doors D1, D2, and D3 is providedwith a safety door switch similar to those sold under the name Omronwith the designation D4DS, D4BS and D4BL Series. Such a switch willindicate whether or not the door is open or closed, typically by use ofa spring loaded pin that will be pushed in and in contact with a set ofcontacts when the door is closed. This will allow voltage to passthrough the switch giving the operator an indication that the door isclosed. Such a switch can be programmed in one or several ways. Forexample, it can be programmed in conjunction with a “fire-eye” or arcsensitive switch so that if hot work is being performed inside theenclosure when the door was accidentally opened, the system wouldautomatically shut down. The switch can also be programmed so that if nohot work was being performed when the door was opened a timing circuitwould allow a predetermined amount of time to pass for the door to beclosed before shutting down the system. If the door were shut in thispredetermined amount of time the system would not shut down.

At least one shatterproof viewing window VW1, VW2, and VW3, will also beprovided for each enclosure for observing workers inside the enclosure.The three enclosures are also in communication with appropriate hot workequipment, such as welding machines and generators WG1, WG2, and WG3,and associated gas tanks T1-T6. The gas tanks will typically containwelding gases such as oxygen and acetylene. Each tank is equipped with,respectively, a shutdown valve V1-V6, which is activated in case of anemergency shutdown by receiving a shutdown signal from the shutdowncontroller 3. Valves V1-V6 will preferably be conventional solenoidvalves readily available in the art. Further, each enclosure is providedwith at least one remote manual emergency shutdown switch RSD1, RSD2,and RSD3. There is also a manual shutdown switch integrated in at leastone of the enclosure controllers EC1, EC2, and EC3 and also for theoperator monitoring the operator controller console 1.

It is within the scope of this invention that pneumatic tools be used inone or more of the enclosures. Such tools will require an air compressorAC1 and associated equipment for running the pneumatic tools, such asvolume tank VT1 and blow-down valve 6. The blow-down valve 6 providesfor the sudden bleeding of compressed air from the compressed air systemin case of an emergency to prevent damage to such things as compressorseals. It also serves to immediately stop the operation of pneumatictools in case of an emergency shutdown.

There is also a blower, B1, B2, and B3 associated with the inlet port ofeach enclosure for providing fresh air to the workers inside theenclosure, as well as for providing a positive pressure differentialinside the enclosure. Although the blowers can be operated electricallyor by use of compressed air, it is preferred that the blowers beelectric blowers. Air is provided from the blowers to the inlet portsvia any suitable hose or ducting C1, C2, and C3. It will be understoodthat the temperature inside of each enclosure can be controlled to somedegree by providing either cool air or heated air into the blowerintake. Cooled or heated air can be provided by any suitable means, suchas by the use of a conventional heat exchange unit at the intake of theblower. It is preferred that each blower have associated therewith itsown independent control device BC1, BC2, and BC3 each of which containsa shutdown relay SDR in communication with said shutdown controller 3but which can be bypassed by the operator at the operator controllerconsole. That is, if the emergency shutdown is not triggered by the gasdetection monitors 4B1, 4B2, and 4B3, at the intake of the blowers, thenthe blowers can be made to continue to operate for the safety of theworkers inside the enclosure. It is preferred that each enclosurecontroller have associated therewith a power controller for controllingpower to receptacles associated with each enclosure. The powercontroller will cut power to the receptacles in the case of a shutdowndisabling all power tools used in and around the enclosure. Each powercontroller, as well as each blower control device will preferablycontain a shutdown relay that is capable of shutting down power inresponse to a shutdown signal relayed to it.

As previously mentioned, each enclosure will also preferably have itsown independently operated enclosure controller EC1, EC2, and EC3. Thiscontroller is a multifunctional unit containing: a) at least one controldevice, preferably one, of the said at least one, being a programmablelogic control device CT; b) an audible alarm AH; c) a visual alarm AL;d) a differential pressure monitor DPM; and e) a manual shutdown switchSD. The enclosure controller will typically be a sealed box of asuitable material containing the predetermined components. The enclosurecontroller box will contain a door that will preferably be fitted with atamper switch that will trigger an audible or visual alarm should thedoor be opened. Non-limiting examples of enclosure controllers used inthe practice of the present invention are shown in FIGS. 4, 5, 6 and 7hereof.

In a preferred embodiment, the enclosure controller will also containone or more of the following items selected from: a) a manual emergencyshutdown switch SD; b) a back-up battery system BB; c) a camera moduleCM; d) a component sensor module SM; e) a power converter supply PS; f)a radio transceiver RT, used for wireless communication; or g) a remotecontrol panel RCP, touch screen application. The component sensor moduleSM will be capable of sensing one or more variables inside of theenclosure controller. Such variables include temperature, humidity, airflow, and sound. It is more preferred that at least the temperature andhumidity be monitored. The enclosure controller can also contain avoltage meter capable of indicating the state of the batteries, whichvoltage can be communicated to the operator controller console.

In another preferred embodiment, the DPM contained in the enclosurecontroller will be an integral device containing: a) a differentialpressure switch; b) a gauge, for a manual readout of the currentdifferential pressure reading; and c) a transmitter for sending a signalto the programmable control device CT for a readout of the currentdifferential pressure reading via a display device.

One type of differential pressure monitor that can be used in thepractice of the present invention is the Explosion Proof DifferentialSwitch, such as the Model 1950, manufactured by Dwyer Instruments, Inc.,of Michigan City, Ind. The interior of the enclosure is at a higherpressure than the pressure outside of the enclosure to prevent flammableor combustible gases from entering the enclosure during hot workoperation. If the pressure inside the enclosure drops to substantiallythe pressure outside of the enclosure, a signal is sent to the shutdowncontroller 3, which sends the appropriate shutdown signal to all weldingequipment, including tank valves, welding machines, etc. There will betimes when workers need to enter or exit the enclosure during normal andsafe working conditions and unless the DPM(s) can be bypassed, anemergency shutdown will occur anytime if the pressure in the enclosuredrops to a level that would be substantially equal to the pressureoutside the enclosure. Thus, a worker wishing to enter or exit anenclosure would communicate with the operator, who would deactivate theDPM for that enclosure until the worker has safely entered or exited theenclosure, upon which it is reactivated. It is within the scope of thisinvention that each enclosure be provided with a device wherein a workerdesiring to enter to exit an enclosure would know the status of the hotwork taking place within the enclosure. That worker can then activate aswitch that would by pass the DPM and allow the door to be openedwithout causing a system shutdown and would allow the worker apredetermined amount of time to enter or exit the enclosure.

The three enclosures E1, E2, and E3, can all simultaneously andindependently be monitored and controlled by an operator monitoring theoperator controller console 1, which is the central control center forall enclosures E1, E2 and E3. The operator controller is in wirelesscommunication, preferably radio communication, with a remote location 11which is also a controller similar to the operator controller. It ispreferred that the radio communication be achieved via a satellite linkSL via a communications satellite SAT. This will enable an operator atthe remote location, which will typically be a land based centraloperation center capable of monitoring and controlling multipleenclosures and multiple location around the world. The central locationcontroller can be used to provide advice or take over the entireenclosure operations during an emergency. The central locationcontroller can also be used to provide software patches and softwareupdates simultaneously at multiple locations around the world. The radiocommunication system can also be used to allow a client, such as a majoroil company, to monitor the hot work being performed on its platform.

It will be understood that the three enclosures are shown in the figureshereof for illustrative purposes only. The present invention can bepracticed for only one enclosure or for any number of enclosures, andall enclosures can be independently and simultaneously monitored andcontrolled. Of course, practical considerations, such as constructiontime, number of workers required, and space limitations will dictate themaximum number of enclosures that can practically be built andsimultaneously operated at any given facility. The operator controllerconsole 1 will contain: a) a suitable means of power, preferably aconventional AC-DC power converter (not shown); b) at least one controldevice, one of those control devices preferably being a programmablelogic controller (PLC). Other non-limiting examples of typical controldevices that can be used in the practice of the present inventioninclude: electrical relays, solenoids, switches, circuit breakers andfuses; c) a suitable means for monitoring the status of any one or moreenclosures and performing certain predetermined control functions, suchas: i) automatically and manually by-passing a differential pressuremonitor (DPM) at each of the enclosures; ii) displaying the status ofdevices being used in the system; iii) providing scaled readings ofparticular devices in the system; and iv) performing control functionsas needed or as programmed; d) a manual emergency shutdown switch thatis capable of shutting all of the enclosures simultaneously; and e) anappropriate audible and visual alarm system. It is preferred that themeans for monitoring the status of any one or more enclosure be asuitable touch screen application having a graphic display andprogrammed with suitable software

The operator controller console 1 is integrally connected to amonitoring system. The monitoring system can be any suitable system thatwill allow communication between the components of the system,preferably the console and the gas detection monitors and preferablywireless communication. The monitoring system is comprised of a gasdetection controller console 2, which preferably contains: a suitableradio modem transceiver; a central processing unit (CPU); a displaydevice; and a plurality of interface cards. Interface cards are wellknown in the art and are typically a circuit board with the appropriatecomponents to allow communication across boundaries, such as betweenhardware, or between software and hardware. Interface cards also allowcommunication between different software languages and codes that anapplication needs to communicate with each other and with hardware. Itis to be understood that the entire gas detection monitoring systemcould be hardwired, although a wireless system is preferred. The displaydevice is preferably part of a portable computer, more preferably alaptop computer. The gas detection monitors 4 are another component ofthe monitoring system and are in constant communication with the gasdetection controller console 2, and are strategically placed within andabout the enclosures as well as in the vicinity of hot work equipment,blowers and any of the other various equipment associated with thepresent enclosure system. It is preferred that at least two gasdetection monitors be located inside each enclosure, at least onelocated near the ceiling and at least one near the floor to better coverthe entire atmosphere of the enclosure. It is also with in the scope ofthe present invention to place gas monitors a distance away, preferablyat least 10 feet away from the enclosure in such a pattern thatsubstantially 100% of the perimeter of each enclosure is monitored bygas detection monitors. These perimeter gas detection monitors will alsobe placed in high and low positions so that gases heavier than air aremonitored as well as gases lighter than air. A remote antenna box AB1,is preferably used for receiving signals (radio frequency) from theplurality of gas detection monitors 4 and carrying them to the gasdetection controller console 2, in the event that it is being used inthe interior of a building.

It is within the scope of the present invention that the software usedfor the gas detection controller console 2 be suitable for labeling eachof the plurality of gas detection monitors as to their physical locationand being viewable via a display device. This will allow the operator toknow immediately what monitor is sending a distress signal which willallow the operator to take immediate appropriate measures at the preciselocation of distress. For example, if the distress signal is not comingfrom a gas detection monitor located in the vicinity of the blowerintake, the operator can over ride the blower shutdown function so thatthe blower continues to conduct fresh air into the enclosure.

As previously mentioned, each gas detection monitor 4 is incommunication with the gas detection controller console 2. The gasdetection monitors 4 are preferably portable and wireless, making themcapable of being carried or worn by workers. Each monitor will beprogrammed to measure one or more non-limiting variables, such astemperature, combustible gases including those represented in the lowerexplosive limit (LEL), oxygen, carbon monoxide, and hydrogen sulfide.Although single point gas detection monitors can be employed, it ispreferred that multi-point monitors be used. That is, a single pointmonitor is capable of monitoring the concentration level of only onevariable, whereas a multi-point monitor is capable of simultaneouslymonitoring the concentration of more than one variable and as a part ofa wireless system the gas detection monitor will simultaneouslycommunicate information to the transceiver of the gas detectioncontroller console 2, which in turn transmits the signal through asuitable interface means, preferably an electronic interface card, thatwill translate the data into a protocol suitable for the software in anassociated CPU to read, analyze, display, store, and respond thereto. Itis preferred that one or more of the gas detection monitors also havethe capability of either two-way voice communication or receiving textmessages as a part of a network. The gas detection controller console 2interfaces with the operator controller console 1 by any suitable means,such as also by the use of a suitable electronic interface card. Theoperator controller console 1 will have the capabilities as previouslymentioned, such as showing the status of each enclosure, etc. The CPU ofthe gas detection controller console will also be capable of sendingshutdown signals to the operator controller console 1, which in turnsends the signal to the shutdown controller 3, which signals thetargeted equipment to shutdown. The ability of an operator to be able tomonitor, on a display device, the concentration of atmospheric variablessuch as gas levels, temperature, etc., allows the operator to take theproper preemptive action prior to a level of emergency being reached. Aspreviously mentioned, the operator controller console 1 will preferablydisplay the status of the enclosure systems, preferably by the use of atouch screen application. That is, a device that has the capability ofbeing programmed to display the status of devices in the system based onpredetermined variables. Any conventional touch screen application maybe used although a color screen is preferred for extended alarm rangenotification through the use of colors for different alarm levels.

An upper concentration level for each atmospheric variable is programmedinto the CPU software and if that level is reached, the system willautomatically shutdown all targeted hot work equipment at all enclosuresvia communication with the shutdown controller 3. The shutdowncontroller 3 is in communication with all systems, devices and equipmentof the overall system. For example, upon receiving an emergency shutdownsignal from the operator controller console 1 via the gas detectioncontroller console 2, a shutdown signal is sent to valves V1-V6 shuttingdown all gas delivery to the welding equipment. A shutdown signal isalso sent to blower controls BC1 to BC3 as well as to the blow-downvalve 6 and welding equipment WG1 to WG3. As previously mentioned, it iswithin the scope of this invention that blowers B1 to B3 continue tooperate if it is determined that an emergency was not caused by thepresence of combustible or flammable gases at the gas detection monitorat the intake of the blowers B1-B3. It is also within the scope of thisinvention that a function be provided that can shutdown all hot work inthe case of a facility shutdown. That is, if a production platform,refinery or other facility has a general emergency shutdown, allhot-work will automatically be shutdown as a part of the facilityshutdown.

In a preferred embodiment, the use of both a wireless gas detectionsystem and some hard wired gas monitors, is used for implementing theautomatic blower control concept.

Other preferred embodiments are represented in FIGS. 2 to 4 hereof. Thecomponents of the gas detection controller console are integrated intothe operator controller console, becoming a system console, and aportable computer is used as a display device, labeled as device (2) inthese figures.

FIG. 2 hereof represents another preferred embodiment of the presentinvention. FIG. 2 further shows the use of a temperature probe TP1, TP2,TP3 and a temperature detector TD1, TD2, and TD3 in the inside of theenclosures E1, E2 and E3. The temperature probe is used to take ambientreadings of the interior of the enclosure. These readings can be used towarn the operator, sound an alarm and/or initiate a shutdown. Thetemperature detectors are used to take temperature readings of an objectbeing used in the enclosures E1-E3. These readings can also be used toperform the functions previously described. All of FIG. 2 componentsthat are common to FIG. 1 have the same nomenclature as those of FIG. 1hereof. FIG. 2 hereof also shows more hardwired connections because ofthe addition of a camera module and a component sensor module as part ofthe enclosure controller. It is preferred in some instances that thesetwo modules be hardwired to the shutdown console and controller console.

FIG. 3 which shows an all wireless monitoring system, represents anotherpreferred embodiment of the present invention. FIG. 4 further shows theuse of a plurality of additional remote antenna boxes AB2-AB6. Theremote antenna boxes are used for wireless communication between thecontrollers being used in the operator controller console 1, theshutdown controller 3 and the enclosure controllers EC1, EC2, and EC3.All of FIG. 3 components that are common to FIG. 3 have the samenomenclature as those of FIG. 2 hereof.

FIG. 4 hereof represents another preferred embodiment of the presentinvention which is substantial all wireless system. FIG. 4 further showsthe use of a plurality of remote control panels RCP1, RCP2, RCP3, andRCP4. These remote control panels are a touch screen application, whichcan be integrated into the shutdown and enclosure controllers or usedremotely from the controllers, i.e. outside of the enclosures E1, E2 andE3 for controlling and viewing certain predetermined functions of thecontrol system. FIG. 4 further discloses the use of an alternate powersource for the shutdown and enclosure controllers. This alternate powersource is preferably in the form of a solar panel SP1, SP2, SP3, andSP4; these devices can be used in lieu of a conventional AC-DC powerconverter supply. All of FIG. 4 components that are common to FIG. 3hereof have the same nomenclature as those of FIG. 3 hereof.

FIG. 5 is a diagram representation of a preferred embodiment of theenclosure controller of the enclosure system represented in FIG. 1hereof. This controller would be used in the inside of the enclosuresE1, E2 and E3. It contains the following components listed: the audiblealarm AH, the visual alarm AL, the controller CT, the manual shutdownswitch SD, the back-up batteries BB and the differential pressuremonitor DPM.

FIG. 6 is a diagram representation of another preferred embodiment ofthe enclosure controller. It shows the components used in the systemrepresented in FIG. 2 hereof. It contains the following additionalcomponents from the controller described in FIG. 5: the camera module CMand the sensor module SM. All of FIG. 6 components that are common toFIG. 5 have the same nomenclature as those of FIG. 5 hereof.

FIG. 7 is a diagram representation of another preferred embodiment ofthe enclosure controller and is the enclosure controller if theenclosure system represented in FIG. 3 hereof. It contains the followingadditional components from the controller described in FIG. 6: the powersupply PS and the radio transceiver RT. All of FIG. 7 components thatare common to FIG. 6 have the same nomenclature as those of FIG. 6hereof.

FIG. 8 is a diagram representation of the enclosure controller of theenclosure system represented in FIG. 4 hereof. It contains the followingexceptions and additional components from the controller box describedin FIG. 7: the power supply PS, has been removed due to the use of thealternate power source or solar panel SP2-SP4 described in FIG. 4, theDPM although still used has been changed to one that also contains agauge for a visual display of the readings being taken, and a remotecontrol panel for transmitting a signal to the operators controllerconsole touch screen application, for viewing of the current readings.All of FIG. 7 components that are common to FIG. 6 have the samenomenclature as those of FIG. 6 hereof.

1. An enclosure system comprised of one or more enclosures built aboutat least one object to be hot worked at a facility wherein flammable orcombustible materials are located within a hazardous distance from wherethe hot work is to be performed, which enclosure system is comprised of:a) at least one enclosure, each enclosure comprising: i) enclosingwalls, ceiling and floor defining a chamber in which the hot work is tobe performed; ii) at least one door to allow workers to enter and exit;iii) at least one air inlet port; iv) at least one air outlet port; v)at least one blower having an intake and exhaust, which exhaust is influid communication with said at least one air inlet port; vi) a blowercontrol in communication with said at least one blower and to a gasdetection monitor at the intake of at least one of said one or moreblowers and to a shutdown controller, wherein said blower control hasthe capability of allowing the blower to continue to operate during anemergency shutdown that is not triggered by a combustible or flammablegas detected at a gas detection monitor located at the intake of saidone or more blower; vii) at least one manual emergency shutdown switchinside of said enclosure; and viii) at least one manual emergencyshutdown switch outside of, but within the immediate perimeter of, saidenclosure; b) a monitoring system comprised of: i) a plurality of gasdetection monitors located at the predetermined locations inside andoutside of each enclosure; wherein each of said gas detection monitorshaving a means of communication with a gas detection controller console;and ii) a gas detection controller console comprised of: a) a meanscapable of receiving data transmitted from the plurality of the gasdetection monitors; b) an interface means capable of communicating datafrom said receiving means of the console to a central processing unit;c) the central processing unit containing software capable of, interalia, accepting, storing computing, and displaying data received fromsaid plurality of gas detection monitors; d) a display device incommunication with said central processing unit and capable ofdisplaying data from said plurality of gas detection monitors; and e) aninterface means capable of communicating a signal from said centralprocessing unit to a control system; c) the control system comprised of:i) an operator controller console comprised of: a) a source ofelectrical power for the system; b) at least one control device; c) ameans for displaying the status of each enclosure; d) a capability ofcommunicating predetermined bypass and system shutdown signals to ashutdown controller; and e) an audible alarm that will activate when ashutdown occurs; ii) a shutdown controller capable of sending shutdownsignals to one or more enclosure control devices, one or more shutdowncontrol devices, and to various equipment associated with the hot workto be conducted in said one or more enclosures; iii) an enclosurecontroller comprised of a differential pressure monitor for monitoringthe pressure within the enclosure relative to the pressure outside ofthe enclosure, a programmable logic control device, an audible alarm anda visual alarm; and iv) a controller console at a remote location and inradio communication with said operator controller console and shutdowncontroller, which controller console is capable of performing all thefunctions of said operator controller console and which is also capableof downloading software said central processing unit and programmablelogic control device.
 2. The enclosure system of claim 1 wherein theradio communication is provided by a satellite link.
 3. The enclosuresystem of claim 1 wherein the door of each enclosure is a breakaway doorthat opens outward.
 4. The enclosure system of claim 1 wherein eachenclosure is provided with an explosion proof interior lighting system.5. The enclosure system of claim 1 wherein the outlet port of at leastone enclosure is provided with a spark resistant filter.
 6. Theenclosure system of claim 1 wherein the hot work to be performed iswelding.
 7. The enclosure system of claim 1 wherein the blower of eachenclosure is an electrically operated blower.
 8. The enclosure system ofclaim 1 wherein at least two gas detection monitors is located in eachenclosure.